SummaryThe connections of the olfactory bulb were studied in the piranha using the Nauta and horseradish-peroxidase methods. Three olfactory tracts project to seven terminal fields in the telencephalon and one in the diencephalon, all of them bilaterally. The contralateral olfactory bulb also receives a small input. All contralateral projections decussate in the anterior commissure and are relatively weak compared to the ipsilateral projections. HRP-containing cells were found in all of the ipsilateral telencephalic aggregates receiving an olfactory tract projection; the contralateral side was free of labeled cell bodies. Although only about one fourth of the entire telencephalon receives a direct olfactory input, the high degree of differentiation of the olfactory system suggests that the piranha depends substantially on the sense of olfaction and that this species may be a good model for further studies on olfactory mechanisms.

中文翻译：

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食人鱼（Serrasalmus nattereri）中嗅球的连接

总结使用 Nauta 和辣根过氧化物酶方法研究了食人鱼中嗅球的连接。三个嗅束投射到端脑中的七个末端区域和间脑中的一个末端区域，它们都是双侧的。对侧的嗅球也接收到一个小的输入。所有对侧投影都在前连合处交叉，与同侧投影相比相对较弱。在所有接受嗅觉投射的同侧端脑聚集体中都发现了含有 HRP 的细胞；对侧无标记细胞体。虽然只有大约四分之一的整个端脑接受直接的嗅觉输入，